What one appliance costs you to run.
£1.05 a day
About £31.58 a month and £384.27 a year, used 2 hours a day.
The power figure is printed on the appliance's label or sticker, usually in W. Space heaters, tumble dryers and kettles use the most; a fridge uses less but never switches off.
Where to find an appliance's wattage
Every appliance has a rating plate or sticker — usually on the back, underneath, inside the door or on the power socket — which lists its power in watts (W) or kilowatts (kW). If it is in kilowatts, multiply by 1,000. Where only amps and volts are shown, multiply them together to get watts.
Some appliances do not run at full power all the time. A fridge, freezer, boiler or air conditioning unit cycles on and off once it reaches temperature, so its wattage is what it draws while running rather than what it uses every hour. For those, a rough estimate of the hours it actually runs is more useful than the hours it is switched on.
What tends to cost the most
Anything that makes heat draws the most power: electric heaters and bar fires around 2,000W, tumble dryers around 2,200W, kettles around 3,000W for a few minutes, and ovens around 2,000W while warming. Anything with a element left on overnight can quietly add a hundred pounds or more to a year. Cooling appliances run all day but at low power, so a modern fridge-freezer is usually far cheaper than a single hour of an electric heater.
Getting a closer answer
This calculator assumes the appliance runs at its rated power for the hours you enter. To check reality, switch everything else off, note your smart meter's kWh reading, run the appliance for a set time and read the difference — that is the exact figure to use. Compare tariffs on the same appliance, and a lower unit rate makes the expensive ones cheaper to run.
The starting rates are Ofgem's price cap averages for 1 October to 31 December 2026 for a default tariff paid by Direct Debit in England, Scotland and Wales, and the starting usage figures are Ofgem's medium-consumption averages. Ofgem's cap is a maximum per unit, not the price you are promised: your supplier sets your rates, they differ by region and meter type, and prepayment customers pay different rates again. Check the unit rate and standing charge on your own bill before you act on anything here.
Next steps
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